Two years ago, BillGuard launched to help consumers identify fraudulent charges on their credit cards. Now it’s hoping to save them money with the launch of a new iPhone app determined to identify and dispute so-called “grey charges” — that is, charges that they might have agreed to but forgot about.

When it comes to grey charges, think free trials that result in subscription charges, for instance. Or your grandmother’s AOL dialup subscription. Those charges are incredibly common, and usually are easy to resolve.

The problem is that most customers don’t pay enough attention to their credit card accounts to know that they’re there or dispute them. According to a study conducted using BillGuard data, there are approximately 233 million grey charges posted to U.S. credit cards every year, resulting in about $14.3 billion lost by consumers annually.

The BillGuard iPhone app seeks to make identifying those charges easier by highlighting new questionable charges users might get. While the BillGuard web product was designed mainly as a set-it-and-forget-it type of application, the iPhone app hopes to keep users engaged with push notifications, letting them know of questionable charges as they pop up.

When they go into the transaction screen, users can verify charges that they’re aware of by swiping right on those charges. For those they’re not sure of, they can choose to get help with a transaction by swiping left. Doing so brings up a screen to help users identify a certain charge or vendor, dispute it, or save for later. Using that information, the app’s smart inbox learns only to highlight new charges from questionable vendors.

When disputing a charge, users don’t need to know much about the company that it came from. BillGuard has a vast database of vendors, and can send an email to the origin of most disputes directly. This saves the consumer time, and it saves the vendor money by having them deal with consumers directly, rather than dealing with the customer’s bank.

Not only does the app help consumers save money individually, but it also helps BillGuard crowdsource data to identify vendors or charges that might be seen regularly by other users of its products. The company has a large amount of crowdsourced data both from its users and from banks it works with to help their users resolve disputes. According to co-founder and CEO Yaron Samid, it has scanned nearly a billion transactions between the two.

The app is free to download and allows users to add up to two credit cards for free. If they want to add more, the app has a one-time charge to manage up to 10 cards for just $9.99.

BillGuard was a finalist at TechCrunch Disrupt a few years ago, and since has raised $13 million in funding from investors that include Khosla Ventures, Founders Fund, Eric Schmidt’s Innovation Endeavors, Bessemer Venture Partners, IA Ventures, Saul Klein and Joe Lonsdale.